Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 297 insertions, 0 deletions

diff --git a/src/basic/extract-word.c b/src/basic/extract-word.c
new file mode 100644
index 0000000..160f771
--- /dev/null
+++ b/src/basic/extract-word.c
@@ -0,0 +1,297 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <syslog.h>
+
+#include "alloc-util.h"
+#include "escape.h"
+#include "extract-word.h"
+#include "log.h"
+#include "macro.h"
+#include "string-util.h"
+#include "strv.h"
+#include "utf8.h"
+
+int extract_first_word(const char **p, char **ret, const char *separators, ExtractFlags flags) {
+        _cleanup_free_ char *s = NULL;
+        size_t sz = 0;
+        char quote = 0;                 /* 0 or ' or " */
+        bool backslash = false;         /* whether we've just seen a backslash */
+        char c;
+        int r;
+
+        assert(p);
+        assert(ret);
+        assert(!FLAGS_SET(flags, EXTRACT_KEEP_QUOTE | EXTRACT_UNQUOTE));
+
+        /* Bail early if called after last value or with no input */
+        if (!*p)
+                goto finish;
+        c = **p;
+
+        if (!separators)
+                separators = WHITESPACE;
+
+        /* Parses the first word of a string, and returns it in
+         * *ret. Removes all quotes in the process. When parsing fails
+         * (because of an uneven number of quotes or similar), leaves
+         * the pointer *p at the first invalid character. */
+
+        if (flags & EXTRACT_DONT_COALESCE_SEPARATORS)
+                if (!GREEDY_REALLOC(s, sz+1))
+                        return -ENOMEM;
+
+        for (;; (*p)++, c = **p) {
+                if (c == 0)
+                        goto finish_force_terminate;
+                else if (strchr(separators, c)) {
+                        if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) {
+                                if (!(flags & EXTRACT_RETAIN_SEPARATORS))
+                                        (*p)++;
+                                goto finish_force_next;
+                        }
+                } else {
+                        /* We found a non-blank character, so we will always
+                         * want to return a string (even if it is empty),
+                         * allocate it here. */
+                        if (!GREEDY_REALLOC(s, sz+1))
+                                return -ENOMEM;
+                        break;
+                }
+        }
+
+        for (;; (*p)++, c = **p) {
+                if (backslash) {
+                        if (!GREEDY_REALLOC(s, sz+7))
+                                return -ENOMEM;
+
+                        if (c == 0) {
+                                if ((flags & EXTRACT_UNESCAPE_RELAX) &&
+                                    (quote == 0 || flags & EXTRACT_RELAX)) {
+                                        /* If we find an unquoted trailing backslash and we're in
+                                         * EXTRACT_UNESCAPE_RELAX mode, keep it verbatim in the
+                                         * output.
+                                         *
+                                         * Unbalanced quotes will only be allowed in EXTRACT_RELAX
+                                         * mode, EXTRACT_UNESCAPE_RELAX mode does not allow them.
+                                         */
+                                        s[sz++] = '\\';
+                                        goto finish_force_terminate;
+                                }
+                                if (flags & EXTRACT_RELAX)
+                                        goto finish_force_terminate;
+                                return -EINVAL;
+                        }
+
+                        if (flags & (EXTRACT_CUNESCAPE|EXTRACT_UNESCAPE_SEPARATORS)) {
+                                bool eight_bit = false;
+                                char32_t u;
+
+                                if ((flags & EXTRACT_CUNESCAPE) &&
+                                    (r = cunescape_one(*p, SIZE_MAX, &u, &eight_bit, false)) >= 0) {
+                                        /* A valid escaped sequence */
+                                        assert(r >= 1);
+
+                                        (*p) += r - 1;
+
+                                        if (eight_bit)
+                                                s[sz++] = u;
+                                        else
+                                                sz += utf8_encode_unichar(s + sz, u);
+                                } else if ((flags & EXTRACT_UNESCAPE_SEPARATORS) &&
+                                           (strchr(separators, **p) || **p == '\\'))
+                                        /* An escaped separator char or the escape char itself */
+                                        s[sz++] = c;
+                                else if (flags & EXTRACT_UNESCAPE_RELAX) {
+                                        s[sz++] = '\\';
+                                        s[sz++] = c;
+                                } else
+                                        return -EINVAL;
+                        } else
+                                s[sz++] = c;
+
+                        backslash = false;
+
+                } else if (quote != 0) {     /* inside either single or double quotes */
+                        for (;; (*p)++, c = **p) {
+                                if (c == 0) {
+                                        if (flags & EXTRACT_RELAX)
+                                                goto finish_force_terminate;
+                                        return -EINVAL;
+                                } else if (c == quote) {        /* found the end quote */
+                                        quote = 0;
+                                        if (flags & EXTRACT_UNQUOTE)
+                                                break;
+                                } else if (c == '\\' && !(flags & EXTRACT_RETAIN_ESCAPE)) {
+                                        backslash = true;
+                                        break;
+                                }
+
+                                if (!GREEDY_REALLOC(s, sz+2))
+                                        return -ENOMEM;
+
+                                s[sz++] = c;
+
+                                if (quote == 0)
+                                        break;
+                        }
+
+                } else {
+                        for (;; (*p)++, c = **p) {
+                                if (c == 0)
+                                        goto finish_force_terminate;
+                                else if (IN_SET(c, '\'', '"') && (flags & (EXTRACT_KEEP_QUOTE | EXTRACT_UNQUOTE))) {
+                                        quote = c;
+                                        if (flags & EXTRACT_UNQUOTE)
+                                                break;
+                                } else if (c == '\\' && !(flags & EXTRACT_RETAIN_ESCAPE)) {
+                                        backslash = true;
+                                        break;
+                                } else if (strchr(separators, c)) {
+                                        if (flags & EXTRACT_DONT_COALESCE_SEPARATORS) {
+                                                if (!(flags & EXTRACT_RETAIN_SEPARATORS))
+                                                        (*p)++;
+                                                goto finish_force_next;
+                                        }
+                                        if (!(flags & EXTRACT_RETAIN_SEPARATORS))
+                                                /* Skip additional coalesced separators. */
+                                                for (;; (*p)++, c = **p) {
+                                                        if (c == 0)
+                                                                goto finish_force_terminate;
+                                                        if (!strchr(separators, c))
+                                                                break;
+                                                }
+                                        goto finish;
+
+                                }
+
+                                if (!GREEDY_REALLOC(s, sz+2))
+                                        return -ENOMEM;
+
+                                s[sz++] = c;
+
+                                if (quote != 0)
+                                        break;
+                        }
+                }
+        }
+
+finish_force_terminate:
+        *p = NULL;
+finish:
+        if (!s) {
+                *p = NULL;
+                *ret = NULL;
+                return 0;
+        }
+
+finish_force_next:
+        s[sz] = 0;
+        *ret = TAKE_PTR(s);
+
+        return 1;
+}
+
+int extract_first_word_and_warn(
+                const char **p,
+                char **ret,
+                const char *separators,
+                ExtractFlags flags,
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *rvalue) {
+
+        /* Try to unquote it, if it fails, warn about it and try again
+         * but this time using EXTRACT_UNESCAPE_RELAX to keep the
+         * backslashes verbatim in invalid escape sequences. */
+
+        const char *save;
+        int r;
+
+        save = *p;
+        r = extract_first_word(p, ret, separators, flags);
+        if (r >= 0)
+                return r;
+
+        if (r == -EINVAL && !(flags & EXTRACT_UNESCAPE_RELAX)) {
+
+                /* Retry it with EXTRACT_UNESCAPE_RELAX. */
+                *p = save;
+                r = extract_first_word(p, ret, separators, flags|EXTRACT_UNESCAPE_RELAX);
+                if (r >= 0) {
+                        /* It worked this time, hence it must have been an invalid escape sequence. */
+                        log_syntax(unit, LOG_WARNING, filename, line, EINVAL, "Ignoring unknown escape sequences: \"%s\"", *ret);
+                        return r;
+                }
+
+                /* If it's still EINVAL; then it must be unbalanced quoting, report this. */
+                if (r == -EINVAL)
+                        return log_syntax(unit, LOG_ERR, filename, line, r, "Unbalanced quoting, ignoring: \"%s\"", rvalue);
+        }
+
+        /* Can be any error, report it */
+        return log_syntax(unit, LOG_ERR, filename, line, r, "Unable to decode word \"%s\", ignoring: %m", rvalue);
+}
+
+/* We pass ExtractFlags as unsigned int (to avoid undefined behaviour when passing
+ * an object that undergoes default argument promotion as an argument to va_start).
+ * Let's make sure that ExtractFlags fits into an unsigned int. */
+assert_cc(sizeof(enum ExtractFlags) <= sizeof(unsigned));
+
+int extract_many_words(const char **p, const char *separators, unsigned flags, ...) {
+        va_list ap;
+        char **l;
+        int n = 0, i, c, r;
+
+        /* Parses a number of words from a string, stripping any
+         * quotes if necessary. */
+
+        assert(p);
+
+        /* Count how many words are expected */
+        va_start(ap, flags);
+        for (;;) {
+                if (!va_arg(ap, char **))
+                        break;
+                n++;
+        }
+        va_end(ap);
+
+        if (n <= 0)
+                return 0;
+
+        /* Read all words into a temporary array */
+        l = newa0(char*, n);
+        for (c = 0; c < n; c++) {
+
+                r = extract_first_word(p, &l[c], separators, flags);
+                if (r < 0) {
+                        free_many_charp(l, c);
+                        return r;
+                }
+
+                if (r == 0)
+                        break;
+        }
+
+        /* If we managed to parse all words, return them in the passed
+         * in parameters */
+        va_start(ap, flags);
+        for (i = 0; i < n; i++) {
+                char **v;
+
+                v = va_arg(ap, char **);
+                assert(v);
+
+                *v = l[i];
+        }
+        va_end(ap);
+
+        return c;
+}